1. Field of the Invention
The present invention relates to an apparatus that displays three-dimensional images, and in particular, to a three-dimensional image display apparatus driven in a time division multiplexing manner.
2. Description of the Related Art
There are various known systems for three-dimensional-vision image display apparatuses that can display three-dimensional motion pictures, that is, three-dimensional displays. In recent years, in particular, there has been a growing demand for a three-dimensional-vision image display system which is of a flat panel type and which does not require any dedicated glasses or the like. In relatively easily feasible known systems, a beam control device is installed immediately in front of a display panel (display apparatus) such as a direct-vision or projective liquid crystal display apparatus or a plasma display apparatus which has fixed pixel positions; the beam control device controls beams from the display panel so that the beams are directed toward an observer.
The beam control device is generally called a parallax barrier. The beam control device controls beams so that different images are visible depending on angle even from the same position on the beam control device. Specifically, a slit array, a lenticular sheet, or a cylindrical lens array is used to provide only a lateral parallax, that is, a horizontal parallax. A pinhole array or a lens array is used to provide a vertical parallax in addition to the horizontal parallax. Moreover, systems using the parallax barrier are classified into a two-view (binocular) type, a multiview type, a super-multiview system corresponding to the multiview type provided with a super-multiview condition, and integral photography (referred to as IP below). The basic principle of these systems is virtually the same as that was invented about 100 years ago and that has been used for three-dimensional photography since then.
For a multiview system or one-dimensional IP (IP with horizontal parallax), there is a tradeoff relationship between viewing zone size, resolution, and depth amount as shown in J. Opt. Soc. Am. A vol. 15, p. 2059 (1998). It is difficult to maintain all the three characteristics at sufficient levels. Thus, a method has been proposed in Jpn. Pat. Appln. KOKAI Publication Nos. 10-206795 and 10-282453; this method can increase one of the viewing zone size, resolution, and depth amount by a factor of n using a time division multiplexing method at the cost of a decrease in luminance to 1/n. However, disadvantageously, this method insufficiently deals with crosstalk for each field resulting from time division multiplexing.
As described above, a problem with the conventional three-dimensional image display apparatus based on the time division multiplexing system is that it insufficiently deals with crosstalk for each field resulting from time division.